benedict hbezog-



(No Model.)

2 Sheets-Sheet 1.

F. B. HERZOG.

TELEPHONE EXCHANGE SYSTEM.

No. 292,115. Patented Jan. 15,1884.

E BENEDICT HERZDG.

G ODE 1 Finn 1e WITNESSES am-ME $44 [NVEN-TUR y n; Aftofnay E f mqy,

am v M N. PETERS, PhoXo-Lllhayflplgr. Washingln D. C.

(No Model.)

F. B. HERZOG.

TELEPHONE EXCHANGE SYSTEM.

2 SheetsSheet 2.

Patented Jan. '15. 1884.

INVENTQR l'lienedict flerzqy, By his .dztorneys N. PETERS Pbowmha nphan Wuhin lan. n. c

TELEPHONE-EXCHANGE SYSTEM.

SPECIFICATION forming part of Letterslatent No. 292,115, dated January 15, 1884, d

' Application filed September 28, 1883. (X0 model.)

To all whom, it may concern.-

Be it known that I, F. Bnunnrcr HERZOG, of the city, county, and State of New York, have invented a new and useful Improvement in Telephone, Exchange Systems, of which the following is a specification:

My invention relates to telephone-exchange systems, where the individual subscribers are put into telephonic communication with each other by an operator at a central office, through which the subscribers circuits pass, and are controlled. Whenever a subscriber is absent from his office, and leaves no one in charge, to inform any one who may then-call, at what timehe intends to return, or where he has gone to, he, at present, generally puts up a notice on the outside of his office door, conveying the desired information. But it frequently happens, that he is detained longer than heexpected, or that he does not wish to returnso soon, or has gone to another place; and then it is often very desirable that he should .at

-.. once be able to change the notice on his door,

so that it shall give the corrected information.

The object of my invention is to accomplish this result, by means of an exchange system. To this end, my invention consists in providing the office of one or more subscribers with a'lcontrivance, which can be seen from outside, when the office is locked, capable of beingset by the subscriber in person, before he leaves his office, so as to indicate the time of his expected return, the place at which he is going, or any other desired information; and which is, moreover so constructed, that it is connected on the subscribers circuit, so that it may also be operated from the central offioe of any telephone, or other electriocircuit exchange, and reset by the operator there, when he is so directed. Then, whenever asubscribor is detained orwishes to remain away longer than he at first intended, he can, by communicating with the central office through any other" subscribers circuit, ask the operator there to reset the indicator at his own office, so as to make the desired change. This, the subscriber is enabled to do by my invention.

In the accompanying drawings, I have illustrated one form of mechanism for carrying out my invention; Figure 1, showing the internal construction of the indicator, placed in some .so that it can be set by the subscriber before leaving, and also by the operator from the central office; Fig. 2, representing the front of an indicator-box comprising several independent indicating-dials, each of which can be independently set at points prearranged to convey any desired information; and Fig. 3, representing a telephone-exchange system with the subscribers offices provided with indicators, according to my invention.

I construct, as follows, this contrivance, by which any caller at the vacant office can obtain the desired information, and which can be set, either by the subscriber at the office before leaving, or by the central-exchange operator at the subscribers direction, when the latter is not there.

A, Fig. 1, represents a metal ratchet-disk with an arbitrary number (in this case fortyeight) of teeth, mounted on a suitable arbor or spindle, so arranged as to be impelled step by step, in the well-known manner, by the pawl D. pivoted to the vibrating lever O. which is actuated by the electro-magnet B. By sending the proper number of electrical impulses over the line through the electromagnet B. from the central office, the ratchet-disk A. may be advanced step by step to any desired position, and by these means the central operator is enabled to set the pointer 11., which is attached to the spindle of the disk A. and moves over the exposed face of the dial, (represented by the dotted lines) in any desired position. The pointer H. is also arranged so that it may be set by hand at the subscribers office. by turning it around with the finger, or by means of a key which his on the squared end of the spindle shown. In order that the central operator may be able to tell, when the pointer is at 0., so that he can set it to theproper position, I attach to the lower end of the vibrating lever 0., a leaf-spring E, the free end of which bears constantly upon the face of the disk A.', and makes electrical connection thereto, except when a strip F. of insulating material, which is sunk flush in the disk in the path of the spring E, comes under theend of said spring, and thereby breaks electrical contact between the spring and disk. 'The lower 0. is represented as drawn forward by the electro-magnet B., the hand H, by the last vibration of the lever 0, having been brought to O. on the dial. Then, when the attraction of the electro-magnet ceases, and the lever O. is drawn back by the retractile. spring K, the free end of the leaf-spring E. slides over the insulatingstrip F., first breaking electrical contact, and then making it again, as the point of the spring comes in contact with the metal of the disk on the other side of the strip F. The main-line circuit after passing through the electro-magnet B, passes through the lever 0., the leafspring E., disk A. and spring G., which makes constant connection to the said disk. Consequently,when thelever O. is on the back stroke, and the hand H. stands at O, the circuit is mementarily broken, but closed again before the lever 0. comes to rest against its back stop, so

as to leave the disk A. ready to be advanced step by step, as before, by impulses sent over the line, from the central office. This momentary break in the circuit, being detected by the central operator, enables him to tell when the hand H. has reached 0. on the dial; but in order that the central operator may detect this break, it is obviouslynecessary that the circuit should remain closed, at the central office, during the back stroke of the lever 0., and therefore the vibration of the lever 0, cannot be produced by simply closing and opening the circuit with a battery on the line, but must be caused by keeping the circuit closed, and increasing and decreasing the strength of eurrent on the line, as I shall hereinafter explain.

In Fig. 3, N. represents the central offiee, to which are connected the several subscribers circuits, and which is provided with the usual annunciator contrivanees to inform the operator there, when each. subscriber calls. Each subscribers office S. S. S. &c., is provided with an indicator, capable of being set from the central office, such as I have already described and illustrated in Fig. 1. At the central oflice, I arrange a circuit comprising a battery 0, and a circuit-closing and opening key P., which key is shunted by a high resistance telephone Q, and this circuit is arranged in the well-known manner, so that it may be connected with any of the subscribers circuits, as desired.

7 The practical working of my invention is.

then as follows:Suppose a subscriber to have set his indicator, and gone to another ofiice, and he wishes to reset his indicator for any reason. He calls up the central office on another subscribers circuit, and tells them how he wishes his indicator set. The central operator thereupon connects the battery 0. and key 1?. to the proper circuit, and, by depressing the key 1?, cuts out the high resistance telephone, and thereby increases the strength of current suffieiently to operate the electro magnet B. \Vhen the key is opened, the resistance of the telephone Q. through which the current has then to pass, weakens the current sufficiently to allow the lever O. to drop back. Thus, the central operator advances the ratchet-disk A. step by step, and sets it at the desired point. By listening at the telephone Q, the operator can detect the momentary break in the circuit, produced when the pointer has reached 0, by

the back stroke of thelcver G.

This device also furnishes a means,whereby the central operator may identify the person who requests him to reset an indicator, so as to be sure that he is a properly authorized person. In resetting the indicator when requested, the central operator can count the impulses required to bring the hand to 0., from which he can deduce at once the number at which the indicator had been set. He can then require the person, requesting to have the specified indicator reset, to give this number together with some other number or pass-word arbitrarily assigned to that office; and as no one but the subscriber himself, or some authorized person, will be able to do this, the 1 number will serve as a basis for a pass-word, which must be given to the central operator, before he will consent to reset the indicator at a different point, from that at which it stood before.

If desired, the indicator may be composed of several different dials, such as I have described, but arranged in the well-known manner to be all operated on the same circuit and set independently from the central ofiice. In Fig. 2, I have shown such an indicator, comprising three dials, each of which may be numbered or marked in any manner to signify different things, as desired. The dials may all be set successively on the same circuit in the well-known manner by suitable mechanism, such as that described in Letters Patent to J. U. Mackenzie, No 273,563, of March 6, 1883. i

It is not essential to my invention, that the indicating contrivances should be placed on the subscriber s telephone-circuits. They may evidently be placed on circuits employed for signaling or calling, or for any other purposes, or they may be arranged on circuits of their own, and worked entirely independently of any other telephonic or signaling apparatus.

I do not confine myself to an indicating contrivance or any particular form of construction, nor to any particular mode of operating such contrivance.

\Vhat I claim as my invention, and desire to secure by Letters Patent is:

1. The combination, in a telephone or telegraph exchange system,with two or more subscribers circuits connected with the central office thereof, and telephonic or telegraphic apparatus whereby the subscribers may communicate with the central olfice, of indicators subscribers, for indicating specified times of sitions at which they'are set, and mechanism located at or near the oiiices of, one or more ICO whereby the said indicators may be set by the operator from the central office, substantially as described.

2. The combination, in a telephone or telegraph exchange system, with two or more subscribers circuits connected with the central office thereof, and telephonic or telegraphic apparatus whereby the subscribers may communicate with the central office, of indicators located at or near the oflices of one or more subscribers, for indicating specified times of day or other information according to the positions at which they are set, means whereby the said indicators may be set by the subscribers at their offices, and mechanism whereby they may be set by the operator from the central office, substantially as described.

3. The combination, in a telephone or telegraph exchange system, with two or more subscribers circuits connected with the central office thereof, and telephonic or telegraphic apparatus whereby the subscribers may communicate with the central office, of indicators located'at or near the oflices of one or more subscribers, for indicating specified times of day or other information according-to the positions at which they are set, means whereby the said indicators may be set by the subscribers at their offices, mechanism whereby they may be set by the operator from the central office, and devices to enable the central operator to tell at what positions the said indicators have been respectively set by the subscribers, substantially as described.

4. The combination,with the metal ratchetdisk A, electro-magnet B, and lever G, for actuating the said disk step by step, of the insulating-strip F in the said disk, and the con necting-spring E carried by the lever G and bearing upon the disk A, so constructed that on the back stroke of the lever 0, when the said disk is at a particular point of its revolution, the springE slides over the strip F, first breaking the circuit and then closing it again before the lever reaches its back stop, 45 substantially as described.

Signed and witnessed this 27th day of September, 1883.

F. BENEDICT HERZOG. Vitnesses:

CHARLES G. CURTIS,

J osnrn M. WILLIAMs. 

